The US Coast Guard released their “2016 Recreational Boating Statistics” report.  The report indicates that recreational boating fatalities increased from 7 in 2015 to 19 in 2016, and fatal accidents rose from 7 to 14.

http://www.seattletimes.com/news/coast-guard-fatal-boating-accidents-double-in-alaska/

For the full report:

http://www.uscgboating.org/library/accident-statistics/Recreational-Boating-Statistics-2016.pdf

Table 32 on page 63 has the year by year summary.